Well yes the Aryan race reference truly does apply if you can't give me a reason beside ethnicity why Christ would separate His brethren. Now in your quote below you mentioned that they were a separate “elite” group from the great multitude which suggest that a few posts ago you did consider them to be first choice or better than the great multitude.
But if you can't give me any reason besides their ethnicity why Christ would separate them from the other saved then it’s saying Christ shows favoritism or partiality among His brethren based solely on their ethnicity. Here you have a great multitude of gentile brethren in the Kingdom of God who are not allowed to sing the same song as their Hebrew brethren:
“They sang as it were a new song before the throne, before the four living creatures, and the elders; and no one could learn that song except the hundred and forty-four thousand who were redeemed from the earth.“
I suppose the gentiles in the Kingdom of God will have to come up with their own song to perhaps woo the Hebrews over to their side with some sweet soulful gospel.
The
reason they are chosen is not said in the text, but we can assume it is not because of their race only, because it doesn't just describe their race, but their actions as well:
4 These are those who did not defile themselves with women, for they remained virgins. They follow the Lamb wherever he goes. They were purchased from among mankind and offered as firstfruits to God and the Lamb.5 No lie was found in their mouths; they are blameless. (Rev. 14:4,5)
It is not based 'solely' on their ethnicity, but based on God's Will.
God
prophesied that these men
would be from the tribes of Israel, not that He chose them
because they were from the tribes of Israel.
You continue to mention this statement that "God doesn't show favoritism" and acting like that is the most important doctrine in the Bible. Didn't God show favoritism when He says "Jacob have I loved, and Esau have I hated."
You are misinterpreting favoritism. God selects whoever He wishes. And if He prophecies them to be from a certain lineage, do you think He did not know it from the foundations of the world?